The Prime Minister said providing homes for people must be the “top priority” over nature and the environment as Government reforms are set to allow more building on the green belt.

A shake-up of planning rules means councils have been given mandatory targets to deliver a total of 370,000 homes a year in England.

Sir Keir Starmer said local plans to reach targets were the starting point, but that the Government would “absolutely” push development through if the plans do not work.

Of course we want to get the balance right with nature and the environment, but if it comes to a human being wanting to have a house for them and their family, that has to be the top priority

Sir Keir said he wanted to “get the balance right with nature and the environment” but that “a human being wanting to have a house” has to be top priority.

The Prime Minister and his deputy Angela Rayner have pledged to build 1.5 million homes and take decisions on 150 major infrastructure projects this parliament.

The updated national planning policy framework (NPPF) commits to a “brownfield first” strategy, with disused sites that have already been developed in the past prioritised for new building.

The default answer when a developer seeks to build on brownfield sites will be “yes” but the Government says these sites will not be enough for the number of homes needed.

Councils will therefore also be ordered to review their greenbelt boundaries to meet targets by identifying lower quality “grey belt” land that could be built on.

The framework defines the grey belt for the first time as green belt land that “does not strongly contribute to green belt purposes”.

Those purposes include limiting urban sprawl, stopping neighbouring towns merging into each other and preserving the special character of historic towns.

Safeguarding the countryside from encroachment and assisting in urban regeneration are no longer included as green belt purposes.

“For years, we have had not enough houses being built. That means that individuals and families don’t have the security that they want,” Sir Keir said during a visit to a construction site in Cambridge.

“We are determined to break through that, to do what’s necessary.

“Of course we want to get the balance right with nature and the environment, but if it comes to a human being wanting to have a house for them and their family, that has to be the top priority.

More specific guidance on how local authorities can assess their green belt land is due to come in January.

Housing minister Matthew Pennycook gave examples of grey belt sites as “disused petrol stations, abandoned car parks, but also just low-value scrub land”, in comments to Times Radio.

Councils are expected to look at releasing higher-quality green belt land for development if they exhaust their supply of brownfield and grey belt.

They can also bring forward higher performing green belt land for development before brownfield and grey belt if they are on “more sustainable” sites, such as around train stations because they promote sustainable transport.

Local authorities will be tasked with drafting plans to meet the targets they have been given and can face consequences if they fail to.

If environmental or infrastructure constraints mean they cannot meet the target, they would need to provide evidence which will then be examined by an independent public inquiry led by a planning inspector acting for the Housing Secretary.

Councils that fail to show plans that can meet targets looking back over the last few years or going forward could also face having a “presumption in favour of development” applied.

Just under one-third of local authorities have adopted a local plan – a document setting out where future homes and infrastructure could be built – within the last five years.

Central Government will also be able to intervene and take over planning if local authorities do not move ahead with making plans.

“The starting point is local plans, and that’s really important for councils to develop the plan according to the target, taking into account local need and working with developers,” Sir Keir said.

“But are we going to push it through if those plans don’t work? Yes we absolutely are.

“Are we going to push away the planning rules and make them clearer, as we have done today, get away the blockers that are stopping the houses being built? Yes, we are absolutely intent.”

Any development on green belt land must comply with new “golden rules”, which require developers to provide infrastructure for local communities, such as nurseries, GP surgeries and transport, as well as a higher level of social and affordable housing.

The Government announced £100 million of additional cash for councils, along with 300 additional planning officers, to speed up decision-making processes.

The extra money can be used to hire more staff or consultants and to carry out technical studies and site assessments.

The NPPF reforms are just one element of the Government’s plans to rewrite the planning rules to make it easier to build homes and major infrastructure projects.

The forthcoming Planning and Infrastructure Bill is intended to rip up red tape and make it faster for projects to be approved.